@Romi and @Tadeus
It's a Sapphire rx470 reference, with blower. So, no dual bios, and no way to see inside without removing the blower

After looking at mine, they DO have dual BIOS - though the switch is not real obvious and tiny.
I wish it would be the same for me, but I triple checked and found nothing.
Maybe different batch from yours ?
Would you be kind enough to take a picture ?